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[en] The temperature control system of calcination furnace KR-260E has been design for calcination process UO2 kernel. The design of the temperature control system is to replace the old damaged control module. The temperature controller of control module used is adjusted to kernel UO2 calcination process with a gradual heating system. The controller is capable of storing 30 heating program patterns and each program can contain up to 10 steps of operation. The functional system test of the calcination furnace KR-260E temperature control system is carried out under no load conditions and is carried out gradually with consideration of the new heating conditions. The functional testing stage is at 200 °C, 300 °C, 450 °C and 600 °C with a 250 °C/hour heating ramp setting, 1 hour temperature soaking and the ramp decreasing to 250 °C/hour. The deviation at 200 °C deviation is 2,7 °C was obtained, at 300 °C the temperature deviation is 1,3 °C, at 450 °C was obtained overshoot is 9,8 °C and the mean temperature deviation is 0.2337 °C, and at 600 °C obtained an overshoot is 10,3 °C and an average temperature deviation is 5.0453 °C. The result of this function test indicates that the furnace can function for kernel UO2 calcination operation. (author)
[en] Automatic translation: In this report, the results of fission product release calculations for the isotopes Cs-137 and Ag-109m, Ag-110m are presented in more detail Nuclear process heating system AVR II were carried out. The concept of Annex AVR II is documented in / 1 / together with important detailed results of the fission product releases. The particle, fuel element and Diffusion data are taken from / 2 /, / 3 / and in the Tables 1 and 2 listed. The same goes for the data too Particle failure and contamination are also shown in the table 1 are listed.
[de]In diesem Bericht werden Ergebnisse von Spaltproduktfreisetzungsrechnungen für die Isotope Cs-137 und Ag-109m, Ag-110m ausführlicher dargestellt, die im Rahmen der Kernauslegung für die Nukleare Prozeßwärmeanlage AVR II durchgeführt wurden. Das Konzept der Anlage AVR II ist in /1/ dokumentiert zusammen mit wichtigen Detailergebnissen der Spaltproduktfreisetzungen. Die zu den Berechnungen notwendigen Partikel-, Brennelementund Diffusionsdaten sind aus /2/, /3/ entnommen und in den Tabellen 1 und 2 aufgeführt. Das gleiche gilt für die Daten zu Partikelversagen und Kontamination, die ebenfalls in der Tabelle 1 aufgeführt sind.
[en] The phase change temperature and latent heat of binary paraffin and fatty acid mixtures were measured using a differential scanning calorimeter. 18 types of samples were found to be suitable for passive walls with phase change temperature ranging from 20 °C to 30 °C. In addition, fifteen types of samples were found suitable for active heating floors or walls with a phase change temperature of 30 °C to 40 °C. Five thousand thermal cycling tests were performed on six representative samples. Based on the experimental results, the average change rates of the phase change temperature of paraffin and fatty acid mixtures were found to be less than 5% and 1%, respectively. These phase change materials exhibited good thermal stability, and the thermal stability of fatty acids was better than that of paraffin mixtures. The appropriate proportions of phase change materials for passive phase change walls and active phase change floors or wall was obtained. (paper)
[en] Automatic translation: 1. Introduction: The central supply of heating has experienced a significant boom in recent years. It is also evident that the increase in the cost of Energy carriers, especially recently, have made significant arguments in favor of the far the expansion of the central heating supply. Due to the better efficiency and the greater freedom of movement in the choice of the heat transfer medium used compared to individual heating systems, the additional costs can be reduced by the Investment for a larger heat distribution and transport network and for the Compensate for any heat losses that occur. The minimum value for the heat consumption density of a certain supply area, which is necessary in order to utilize a heat distribution network sufficiently and thus make it economical, will thus continue to fall if the energy source becomes more expensive. This will make it possible to cover larger areas with lower, hitherto uneconomical consumption density via a distribution network To supply heat or to bring this heat over greater distances.
[de]1. Einleitung: Die zentrale Versorgung mit Heizwärme hat in den letzten Jahren einen erheblichen Aufschwung erlebt. Ebenso ist es offensichtlich, daß die Verteuerung der Energieträger gerade in der letzten Zeit erhebliche Argumente für den weitem ren Ausbau der zentralen Heizwärmeversorgung liefert. Durch den besseren Wirkungsgrad und durch die größere Freizügigkeit bei der Wahl des eingesetzen Wärmeträgers im Vergleich zu Einzelheizungen lassen sich die Mehrkosten durch die Investition für ein größeres Wärmeverteilungs- und Transportnetz und für die auftretenden Wärmeverluste kompensieren. Der Mindestwert für die Wärmeverbrauchsdichte eines bestimmten Versorgungsgebietes, der erforderlich ist, um ein Wärmeverteilungsnetz ausreichend auszulasten und damit wirtschaftlich zu machen, wird somit bei einer weiteren Verteuerung der Energieträger weiter sinken. Hierdurch wird sich die Möglichkeit ergeben, größere Gebiete auch mit niedrigerer, bislang noch unwirtschaftlicher Verbrauchsdichte über ein Verteilungsnetz mit Wärme zu versorgen bzw. diese Wärme über größere Entfernungen heranzuführen.
[en] Fusion power offers the prospect of an almost inexhaustible source of energy for future generations. Although this may be true, it also presents so far serious scientific and engineering challenges. Breeding Blanket is one of key components of future fusion reactors, since it directly involves tritium breeding and energy extraction, both of them critical to development of fusion power. To deal with the development of Breeding Blankets, ENEA (Italian National Agency for New Technologies, Energy and Sustainable Economic Development) designed and built a lead lithium loop (IELLLO: Integrated European Lead Lithium Loop): the experiment aims to support R and D activities for the conceptual and preliminary design of the European test blanket systems. IELLLO was completed, installed and operated at ENEA Brasimone Research Centre. The purpose of this work is to describe the experimental activities that have been carried out concerning the qualification of the facility, and relative instrumentations, for lead lithium applications. A series of thermo-hydraulic investigations on IELLLO facility has been elaborated: lead lithium pressure transducers, heat exchanger, permanent magnet pumping system, mass flow meters and air cooler have been tested. The absolute pressure meter in contact with Pb-16Li was qualified in pressure range up to 10 bar and temperature up to 400 deg. C. The installation of new kinds of Pb-16Li differential pressure transducers will allow to check the pump characteristic curve and accurately calculate valves pressure drops. These factors could give a better information for the thermo-hydraulic qualification of the facility. Vortex Mass Flow Meter has shown good results in terms of accuracy. The performance has been validated by thermal balance with a dedicated heating system. Nevertheless, the installations of different types of mass flow meters will enable to test IELLLO at ITER relevant conditions, and at lower mass flow rates than those tested up to now. The new pumping system with a PM Pump, was qualified for the first time in Pb-16Li, and the procedure for the operation and maintenance of the pump was developed. The pump is able to supply a mass flow rate in the range from 1.2 to 2.4 kg/s with a temperature of Pb-16Li up to 550 deg. C in the test section. Significant results have been obtained also for the heat exchanger, which has shown high efficiencies, even more than expected. Likewise, the Air Cooler has been verified to be able to cool Pb-16Li in a relatively short time, even at the worst temperature and mass flow conditions. (authors)
[en] This study was conducted in order to assess the exposure to bacterial and fungal bioaerosols in the air of waterpipe cafés (AWPCs), in the hose of waterpipe (HWP), and in the water bowl of the waterpipe (WBWP) and to investigate the factors influence increasing the contamination levels in waterpipe cafés in Ardabil. From all the 50 cafés studied, the samples were taken from air and from water contained in water bowl and hose for bacterial and fungal analyses. The results demonstrated that the mean numbers of bacteria and fungi in the indoor air of café, hose, and water bowl were 33.90 ± 14.86 and 25.24 ± 1.99 CFU/m3, 72.16 ± 29.55 and 72.78 ± 42.45 CFU/plate, 53.7 ± 25.46 and 25.26 ± 13.94 CFU/ml, respectively. The predominant bacterial genera in waterpipe cafés were Pseudomonas and Bacillus in air, Staphylococcus and Pseudomonas in the hose, and Staphylococcus and Pseudomonas in the water bowl, respectively. The predominant fungal species in waterpipe cafés were Penicillium and Cladosporium in air, yeast and Fusarium in the hose, and Paecilomyces and yeast in the water bowl, respectively. The results of statistical analysis showed that there was a significant relationship between the mean concentrations of bacterial aerosol and qualitative variables such as type of heating system, materials of wall and ceiling, traditional restaurants, interior supermarkets, moisturized walls, the number of people, area of cafés, and temperature. But there was no significant relationship between these variables and the mean concentration of fungal aerosols. The results also showed that the levels of bioaerosols were high in the air, hose, and water bowl of the waterpipe. Therefore, cafés can be a potential source for the transmission of pathogenic agents and increase the risk of respiratory diseases among waterpipe smoking individuals.
[en] Automatic translation: The discussion about the future of the high temperature reactor was on 1981 revived strongly. It was on the side of industry and economy the question of a THTR follow-up project in the foreground, while the Jülich nuclear research facility is once again very intensively with the long-term role of the Has dealt with high temperature tractor. The considerations of the KFA show that the strategic importance of the high temperature reactor in the field of high temperature energy technology lies because the high temperature reactor is the only nuclear system is that, at sufficiently high temperatures, it can provide heat for environmentally friendly refinement even of inferior fossil primary energy sources. The analysis of the KFA shows further that the technical preparatory work proceeding so well that the next step is the demonstration of nuclear heat extraction. In the fall of 1981 the KFA therefore informs its project partners and supervisory bodies about it informs that she will consider an ''AVR II'' to serve this purpose. In the meantime, the concept for such an AVR II developed. It is described in this report and is intended to serve as the basis for the upcoming discussions with the partners. The AVR II is based heavily on the ''Prototype system Nuclear process heat'' and Nuclear remote energy and builds on the nuclear experience of the AVR I. The concept is not up yet special requests of potential operators or manufacturers optimized, so it can still be designed. The system design presented in the report and the data specified - right up to the Output size - serve for the specification, not the final determination. We hope that the report will provide a good basis for future discussions with our partners a common, sustainable and realizable design of the Concept.
[de]Die Diskussion über die Zukunft des Hochtemperaturreaktors wurde 1981 wieder stark belebt. Dabei stand auf seiten von Industrie und Wirtschaft die Frage nach einem THTR-Folgeprojekt im Vordergrund, während sich die Kernforschungsanlage Jülich noch einmal sehr intensiv mit der langfristigen energiepolitischen Rolle des Hochtemperaturraktors auseinandergesetzt hat. Die Überlegungen der KFA zeigen, daß die strategische Bedeutung des Hochtemperaturreaktors auf dem Gebiet der Hochtemperatur-Energietechnologie liegt, da der Hochtemperaturreaktor das einzige nukleare System ist, das Wärme bei ausreichend hohen Temperaturen zur umweltfreundlichen Veredelung auch minderwertiger fossiler Primärenergieträger bereitstellen kann. Die Analyse der KFA zeigt weiter, daß die technischen Vorarbeiten so gut vorangehen, daß als nächster Schritt jetzt die Demonstration der nuklearen Wärmeauskopplung ansteht. Im Herbst 1981 hat die KFA ihre Projektpartner und Aufsichtsgremien daher darüber informiert, daß sie über einen AVR II nachdenken wird, der diesem Zweck dienen soll. In der Zwischenzeit wurde das Konzept für einen solchen AVR II erarbeitet. Es ist in diesem Bericht beschrieben und soll als Grundlage für die nun anstehenden Diskussionen mit den Partnern dienen. Der AVR II orientiert sich stark an den Projekten Prototypanlage Nukleare Prozeßwärme und Nukleare Fernenergie und baut auf der nuklearen Erfahrung des AVR I auf. Das Konzept ist noch nicht auf spezielle Wünsche potentieller Betreiber oder Hersteller optimiert, es ist also noch gestaltungsfähig. Die im Bericht dargelegte Systemauslegung sowie die angegebenen Daten - bis hin zur Leistungsgröße - dienen der Konkretisierung, nicht der endgültigen Festlegung. Wir hoffen, daß der Bericht eine gute Basis darstellt, um in den kommenden Diskussionen mit unseren Partnern zu einer gemeinsamen, tragfähigen und realisierbaren Gestaltung des Konzeptes zu gelangen.
[en] Automatic translation: With the proposal to convert the Jülich AVR into a nuclear process heating system The aim is to provide an inexpensive demonstration and System testing of the extraction of process heat from a high-temperature reactor at a high usage temperature. The renovation is planned so that the AVR successively different conversion processes as nuclear Can serve heat source, the methane-steam reforming with a tube gap furnace and a process steam generator being provided as an element of direct heat extraction in a process engineering process for the first operating phase. Other coal refining processes are planned for further operating phases. With the completion of the preliminary planning phase, the following essential results can be shown: 1. New system concept The new system concept represents an extension of the existing system dar: A process heat circuit is housed in an extension. Thereby The following system features are mainly implemented: - Minimal changes to the AVR construction through use existing flange connections for the primary circuit feed-through, - high flexibility and extensive accessibility in the area the process heat circuit by arranging the new circuit in a separate building, - Extensive safety-related decoupling of the new and Part of the old system.
[de]Mit dem Vorschlag, den Jülicher AVR zu einer nuklearen Prozeßwärmeanlage umzubauen, wird das Ziel verfolgt, eine kostengünstige Demonstration und Systemerprobung der Auskopplung von Prozeßwärme aus einem Hochtemperaturreaktor bei hoher Nutzungstemperatur zu erreichen. Der Umbau ist so geplant, daß der AVR nacheinander verschiedenen Umwandlungsprozessen als nukleare Wärmequelle dienen kann, wobei für die erste Betriebsphase die Methan-Wasserdampf-Reformierung mit einem Röhrenspaltofen und einem Prozeßdampferzeuger als Element der direkten Wärmeauskopplung in einen verfahrenstechnischen Prozeß vorgesehen ist. Für weitere Betriebsphasen sind andere Kohleveredlungsprozesse geplant. Mit dem Abschluß der Vorplanungsphase können folgende wesentliche Ergebnisse aufgezeigt werden: 1. Neues Anlagenkonzept Das neue Anlagenkonzept stellt eine Erweiterung der bestehenden Anlage dar: Ein Prozeßwärmekreislauf wird in einem Anbau untergebracht. Dadurch werden vornehmlich folgende Systemmerkmale realisiert: - minimale Änderung an der AVR-Konstruktion durch Nutzung vorhandener Flanschanschlüsse zur Primärkreisdurchführung, - hohe Flexibilität und weitgehende Zugänglichkeit im Bereich des Prozeßwärmekreislaufes durch Anordnung des neuen Kreislaufes in einem separaten Gebäude, - weitgehende sicherheitstechnische Entkopplung des Neu- und Altanlagenteils.
[en] Hanford's 242-A Evaporator has had the mission of reducing waste volume in the Hanford Tank Farms since the late 1970's. At the very heart of the 242-A evaporation process is the E-A-1 reboiler, a heat exchanger which adds heat to the waste, and the vacuum condenser system, a three-stage condenser/ejector system which condenses the waste vapors and provides the vacuum at which the evaporation process operates. Over a long period of time, significant degraded performance has been observed in the heat exchangers in both the heating system and in the vacuum condensing system. This degraded performance was indicative of degraded conditions in equipment and/or piping associated with both the heating and vacuum condenser systems. However, in searching for degraded condition in these systems, 242-A engineering also discovered that both systems contained design errors in the condensate drainage associated with all heat exchangers in both systems. By addressing the condensate design errors in addition to correcting the degraded conditions, system performance was restored and even possibly improved. All heat exchangers in the heating and vacuum condensing systems are shell and tube type heat exchangers. Both have liquid on the tube side and vapor on the shell side (in the case of the reboiler the liquid is tank waste and the vapor is 10 lb heating steam, and in the case of the vacuum condensers the liquid is cooling water and the vapor is waste vapor). In both systems, engineering proposed that the vapor condensate was backing up into the heat exchanger, resulting in added poor performance. By focusing on basic heat exchanger system design, projects were initiated to redesign the condensate drainage of these systems and re-plumb the condensate drain lines. Data collected before and after the replumbing provides evidence that the corrected drain lines from the heat exchangers improved the performance of the system as a whole, and in the case of the reboiler, removed a potentially damaging steam condensate water hammer condition. (author)
[en] Solar dryers have become important components for the delivery of dried agricultural products of high quality. They generally are designed to maximize the production of a heating system based on solar radiation. This study involved the design, building and testing of a control system to allow the monitoring of temperature, solar radiations and control of humidity in a Photovoltaic (PV)- Greenhouse Solar Dryer (PVGSD). This was accomplished by assembling a solar charge controller, three solar panels, a power inverter, and a battery system. An Arduino UNO Rev3, DHT22-sensor, solderless breadboard, Liquid Crystal Display (LCD) screen, jumper cables, LightEmitting Diode (LED) red, Global System for Mobile (GSM) communication module, 10k Ω, 220 Ω and 1k Ω resistors and two 5V one channel relays formed the control system. These were assembled in a multi-functional workstation linked to the solar dryer. The GSM communication module was an innovation to allow connection to the internet over General Packet Radio Service (GPRS) network and send/receive SMS. It was used to control the fans remotely and further allowed logging of periodic sensor data (temperature, humidity, voltage and solar radiation values) by sending SMS to a phone number and server. Dryer and product characteristics were measured including temperature, humidity, solar radiation and moisture content. The temperature and humidity profile were monitored for 11 days in the empty PVGSD without the workstation and Open Sun Drying (OSD) showed that the PVGSD recorded the highest temperature of 69oC occurring between 12:00 and 14:00 hours GMT while the OSD recorded at 41.5oC. The highest relative humidity recorded in the PVGSD was 75.5% and 83% for OSD observed at night from 20:00 hours to 5:00 hours GMT. Two commodities, cassava (slices and chunks) and red pepper were dried to evaluate the dryer efficiency, and this was compared with OSD and existing greenhouse type solar dryer (GSD). The cassava slices dried faster than the cassava chunks in all the drying methods indicating that sample size influenced drying rate. PVGSD had a faster drying rate for cassava slices of 0.0732g/g.h compared to 0.04908g/g.h for GSD and 0.02074g/g.h for OSD, while drying rate of PVGSD, GSD and OSD for cassava chunks were 0.0457g/g.h, 0.0355g/g.h and 0.01667g/g.h respectively. Similarly, PVGSD was observed to obtain the highest rate of drying for red pepper of 0.097g/g.h compared to GSD of 0.094g/g.h and OSD of 0.047g/g.h. The drying method, time and sample size were found to have statistical significance (p<0.05) on temperature, moisture content, humidity and drying rate. The PVGSD dryer with the workstation was able to keep the humidity conditions in the dryer low to prevent moisture uptake during the night. The samples in this dryer showed consistent drop in moisture content throughout the drying period. To further evaluate the drying effect on the samples, laboratory analyses such as water activity, color profile and particle size determination were performed on the resultant dried cassava flour samples and red pepper (whole). cassava slices dried faster than the cassava chunks in all the drying methods indicating that sample size influenced drying rate. PVGSD had a faster drying rate for cassava slices of 0.0732g/g.h compared to 0.04908g/g.h for GSD and 0.02074g/g.h for OSD, while drying rate of PVGSD, GSD and OSD for cassava chunks were 0.0457g/g.h, 0.0355g/g.h and 0.01667g/g.h respectively. Similarly, PVGSD was observed to obtain the highest rate of drying for red pepper of 0.097g/g.h compared to GSD of 0.094g/g.h and OSD of 0.047g/g.h. The drying method, time and sample size were found to have statistical significance (p<0.05) on temperature, moisture content, humidity and drying rate. The PVGSD dryer with the workstation was able to keep the humidity conditions in the dryer low to prevent moisture uptake during the night. The samples in this dryer showed consistent drop in moisture content throughout the drying period. To further evaluate the drying effect on the samples, laboratory analyses such as water activity, color profile and particle size determination were performed on the resultant dried cassava flour samples and red pepper (whole). The color profile of red pepper flour and cassava flour from the PVGSD was observed to be better in terms of the redness (a * ) for red pepper, lightness (L * ) for cassava, browning index (BI) and color change (∆E). The color change of red pepper for PVGSD, GSD and OSD were 11.94, 16.43 and 25.25 respectively. The color change of cassava slices for PVGSD, GSD and OSD were 10.49, 10.84 and 11.59 respectively, while that for cassava chunks recorded at 10.60, 12.09 and 12.11 respectively for PVGSD, GSD and OSD. The SD50 values for flours from the slices were finer than those from the chunks. The SD50 values for cassava slices under PVGSD, GSD and OSD were 62 µm, 76 µm and 78 µm respectively, while SD50 values for cassava chunks under PVGSD, GSD and OSD recorded at 80 µm, 92 µm and 106 µm respectively. In general, cassava slices under the three drying methods demonstrated a better quality than the chunks in terms of color and particle size. All samples were dried to a water activity below 0.500 to prevent microbial spoilage. Final water activity for red pepper was 0.384, 0.388 and 0.414 respectively for PVGSD, GSD and OSD, while that for cassava slices and chunk for PVGSD was 0.361 and 0.415 respectively, GSD was 0.384 and 0.446 respectively and OSD recorded at 0.421 and 0.490 respectively. To further understand and describe the drying curves for the samples under the three drying methods, 12 Thin Layer Mathematical models were evaluated. The best model under this study for red pepper is the Midilli and Kucuk model under both PVGSD and GSD while Logarithmic model describes best under OSD. Approximation of diffusion model can be used for cassava slices under PVGSD and GSD, while Midilli and Kucuk model for OSD. These models were selected according to the lowest Root Mean Square Error (RMSE) and chi square (χ 2 ) and highest correlation coefficient (R2). (Author)